Tranny temp while towing too high?

[AZjeff]

I use an 05 GMC Sierra 1500/5.3 2wd xcab to tow a small 5th wheel. Recently moved up from a 3000 lb dry trailer to a 4500 lb dry trailer. With the smaller one the transmission could lock up in OD at 65 mph and I'd see temp around 160, going to 180 in moderate hills and tops at 205 on long pulls uphill. With this heavier trailer I'm seeing 180 on flat ground and the truck runs in 3rd gear mostly and recently on a long interstate uphill it reached 210 and stayed there until I reached the campsite after 10 miles of 25 mph uphill dirt road after exiting the interstate, probably 45 minutes @ 210. 69K on the truck, had a synthetic flush @ 50K. I have a Flex-a-lite cooler on the way that should help but is it enough? Is that kind of temp something to worry about or not? I installed a gauge so the temps are accurate.

 

[kballowe]

Just wondering - what were the ambient temperatures when you were doing this?

No, those transmission temps are not excessive. Yes, a transmission cooler is always helpful in situations like yours.

Next Opinion....

 

[AZjeff]

Originally Posted By: kballowe
Just wondering - what were the ambient temperatures when you were doing this?

No, those transmission temps are not excessive. Yes, a transmission cooler is always helpful in situations like yours.

Next Opinion....



I'd see those temps with the small trailer when it was 110 out pulling to San Diego through Yuma. This first trip with the bigger trailer it was mid 90s.

 

[Trav]

Nothing to get worried over in those ambient temps.
Maybe put a couple of bottles of Lubeguard red in the transmission, it helps, really.

 

[HTSS_TR]

I agree. Lubeguard red is very good transmission additive for not too much money if you buy it in quart bottle. I have it in all my Automatic Transmissions.

 

[oggb]

+1 for Lubegard Red and a transmission cooler.

 

[mechtech2]

Try to keep it at about 175F.
The cooler will help.
At 210, it is not a horrible death sentence. It is a little high.
Fluid will break down easier - there will be some effect. A full synth counteracts this somewhat.

 

[marc1]

Originally Posted By: Trav
Nothing to get worried over in those ambient temps.
Maybe put a couple of bottles of Lubeguard red in the transmission, it helps, really.


Trav - Do you recommend LGR for Dex VI applications as well? I used LGR in my 87 Silverado (700R4, regular Dex) and it was excellent. I have been thinking about it for my 06 GMC (4L60E, Dex VI). What do you think?

 

[Trav]

Yes 100%! It proved to lowers transmission fluid temps with Dex VI and the new Dex VI compatible MaxLife on the scan tool under identical operation parameters in the same cars.
This was in a 4T65E and 4T65E HD, the 4L60E will appreciate it.
I found 2 10 oz bottles in a 12-14 qt system had a significant improvement over 1 bottle.

 

[weebl]

I wouldn't be overly worried with the 210F peak. I saw higher peaks on mine towing up very steep grades, though thankfully that is rare. I am working on getting a transmission cooler though, (not rushing, I think I can get connected through family for one at wholesale), since my vehicle is seeing around 215F (hot line from the transmission) without towing, when ambient temps are in the 90F range, stop and go traffic and AC full blast. Extended temps like that have me a little concerned, but in your situation, doesn't sound like it's happening too much.

So yes, in short, your cooler should help and you should be happy with the results.

 

[mechtech2]

weebl-
Transmission temps are 'standardized' from the sump.
This is the normal location as a reference.
Line temps can be all over the place.

 

[Jim Allen]

Originally Posted By: Trav
Yes 100%! It proved to lowers transmission fluid temps with Dex VI and the new Dex VI compatible MaxLife on the scan tool under identical operation parameters in the same cars.
This was in a 4T65E and 4T65E HD, the 4L60E will appreciate it.
I found 2 10 oz bottles in a 12-14 qt system had a significant improvement over 1 bottle.


Where can I read the proof? I'm not being facetious, just curious.

 

[4Kings]

Are you putting it in 3rd or letting the transmission hunt for 3rd while you're in OD?

A hunting transmission will generate more heat than if you put it in 3rd while climbing, or 2nd for that matter.

 

[Trav]

Seeing both units are in my personal cars and it was my scan tool i guess you have to take my word for it or not, i have nothing to gain or lose by posting my own observations.
Lubeguard has lots of info available.

http://www.lubegard.com/pdfs/downloads/LubegardProductGuide.pdf

 

[Jim Allen]

Might be worth trying in mine, since I can monitor temps in two places and can datalog them. Thanks.

 

[AZjeff]

I added a Flex-a-Lite 5x15 tube&fin cooler directly under the factory cooler and inline after the factory cooler. Also added 1 bottle of LubeGuard Red. Only 1 trip so far (no trailer), 100 miles with ambient temps from 75 - 85 including a 7 mile, 2000' uphill. Temp gauge held steady at 125 deg. Big test this weekend, trip to the North Rim of the Grand Canyon. Lots of uphill 4 lane plus a stout pull up to Jacob Lake.

It looks like it dropped 25 degrees so hoping to keep it under 190 with the trailer.

 

[Trav]

Sounds good but one bottle is not enough. 1 oz per qt of fluid is the minimum amount for LG to have much of an effect.
You have a pretty large fluid capacity in that truck another bottle wont hurt, don't worry about a 10oz overfill.

 

[SteveSRT8]

Should be 4L65E in that vehicle. Big improvements to the trans, much more durable than the 4L60E.

It should also have a trailer tow button. Are you engaging that? It will help your temps also.

 

[AZjeff]

No, it's got a 4L60E transmission. Yes I use the tow button.

Trav, you say you can see the effects of using LGR in your vehicles. What difference do you observe?

 

[SteveSRT8]

Originally Posted By: AZjeff
No, it's got a 4L60E transmission. Yes I use the tow button.

Trav, you say you can see the effects of using LGR in your vehicles. What difference do you observe?


Ouch. I wonder why my 2005 Silverado has the 4L65E? Do you know the differences?

Anyways, Trav has used his scan tool to show significant temp drops when LGR is added. We use it now based on his observations and agree.